“So…you cracked a tooth, did you?” I shook my head. “Well I recently underwent some surgery, and I believe that they had to anchor some tubes and such to my teeth, and I lost a filling as a result.” The dental assistant nodded encouragingly. I wondered for a moment if this was because she couldn’t fail to see the ugly, curving scar which ploughs a furrow through my already thinning hair, and was drawing a not-unreasonable conclusion about my grasp on reality. Ah well, I thought, such is life after brain surgery.Two minutes later, she was staring at my tooth using her tiny mirror-on-a-stick. “Which tooth is it again?” she said, setting off a tiny but improbable alarm somewhere in the darkest reaches of my mind. “It’sch gak gonn.” I said with my mouth wide open, and pointing with my tongue. “Just point to it with your tongue.” she said, skating on very thin ice. In frustration I used my finger instead, succeeding only in pointing to the wrong one (be fair now; how often do any of us point to one of our own teeth?), and quickly reverting to using my tongue. “Gak gonn.”“Riiiight” she said, adjusting her angle of attack. “Hmmm. Be right back.” The little, distant alarm rang once again as her footsteps receded.Despite advancing years and the infuriating tendency for forests of hairs to sprout from my ears, I have excellent hearing. Snatches of puzzled whispering floated through the background noise of drilling and suctioning to reach me; “…lost a filling, but I can’t…” “Did you ask him to…?” “Yes, but I don’t think that…”. My little alarm bell was beginning to sound more like Big Ben. To nobody within hearing range, I laughed nervously.Thirty seconds later I was watching my dentist – a young lady whose incredibly gentle ministrations had mightily impressed me several months earlier – as she threateningly (it seemed to me) pulled on some latex gloves and asked me again why I had chosen to darken their workplace doorstep. I explained again – now with an uncertain smile – what I believed had happened, and pointed (successfully, this time) to the offending premolar. She smiled indulgently, produced one of her instruments of torture and leaned over me. “Let’s take a look.”She poked the errant tooth. “This one?” “Gekk.”“Hmmm.”A minute or two later, as I listened to her explain that I hadn’t lost a filling after all, that the tooth in question bore no signs of ever having been filled, and that (this was in her tone rather than an explicitly expressed statement) I was clearly a buffoon of the highest order, I began to giggle like a naughty schoolboy. I was still chortling when, in order to save face as much as anything else, I made an appointment for a clean and thorough check-up in two weeks’ time.Some things – in this case, my talent for making a fool of myself – never seem to change…